What voltage drop percentage should I use in the UAE?

Use 3% for lighting circuits 4-5% for power circuits (socket outlets, motors, equipment). These limits ensure equipment operates within manufacturer specifications and comply with local utility regulations. Lower voltage drop also means less wasted energy.

Does the calculator work for both copper and aluminum cables?

Yes. Select your conductor material in the calculator. Aluminum has higher resistivity than copper, so it requires larger cross-sections for the same current. Aluminum is common in large industrial feeders where weight and cost savings offset the size increase.

How accurate is this wire size calculator?

The calculator uses industry-standard formulas based on BS 7671 and IEC 60364-5-52. Results are accurate for typical installations. However, special conditions—hazardous areas, buried cables, or unusual installation methods—require professional engineering assessment.

What's the difference between AWG and mm² sizing?

AWG (American Wire Gauge) is used primarily in North America. The UAE follows metric standards where cable size is expressed in square millimeters (mm²). The calculator provides both measurements for reference. For example, 4 mm² is approximately equivalent to 12 AWG.

Why does temperature affect wire sizing in the UAE?

Electrical resistance increases with temperature. In the UAE's hot climate (ambient temperatures regularly exceed 40°C), cables heat up more during operation. This reduces their safe current-carrying capacity. The calculator adjusts for operating temperature to provide appropriate sizing. Learn more about voltage relationships in electrical systems .

Can I use this for solar panel wiring?

Yes. For DC solar circuits, select "DC" as the circuit type. Solar installations often have long cable runs from panels to inverters, making voltage drop a critical factor. The calculator handles both AC and DC systems. For complete solar planning, use the photovoltaic system sizing tool .

What if my calculated size falls between standard sizes?

Always round up to the next standard size. Standard metric sizes include 1.5, 2.5, 4, 6, 10, 16, 25, 35, 50, 70, 95, 120, 150, 185, 240, and 300 mm². Never round down—undersized cables create safety hazards.

Do I need to consider cable length differently for three-phase circuits?

Three-phase balanced loads have different voltage drop characteristics because current flows through all three conductors without a neutral return. The calculator automatically adjusts the formula when you select three-phase operation, using the √3 factor instead of doubling the length.

Wire Size Calculator UAE – Find the Right Cable Size

Parameter	Value
Circuit Type	--
System Voltage	--
Load Current	--
Cable Length (one-way)	--
Conductor Material	--
Adjusted Resistivity	--
Max Allowed Voltage Drop	--
Actual Voltage Drop (with recommended size)	--
Temperature Derating Factor	--

Why Use a Wire Size Calculator?

Choosing the wrong cable size leads to serious problems. Undersized wires overheat, trip breakers, and create fire hazards. Oversized cables waste money and complicate installation. This calculator removes guesswork by computing the minimum wire cross-section based on your specific requirements.

Key benefits of using this tool:

Safety compliance: Ensures cables meet UAE electrical regulations and BS 7671 standards
Voltage drop control: Keeps voltage loss within the 3-4% limit mandated by local authorities
Cost optimization: Avoids overspending on unnecessarily thick cables
Project planning: Provides instant results for residential, commercial, and industrial applications

The tool factors in conductor material (copper or aluminum), circuit type (single-phase or three-phase), cable length, and ambient temperature—critical for the UAE's hot climate where standard ratings don't always apply. For accurate electrical power computations, understanding wire sizing is essential.

ADVANCED WIRE SIZE CALCULATOR FOR UAE Compatible with WordPress Elementor HTML Widget Version: 2.0 - Compliant with DEWA, ADDC, SEWA Standards Supports: Single-phase, Three-phase, DC circuits Features: Voltage drop, ampacity check, temperature derating, AWG/mm² conversion

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📊 Calculate Button Results Container Main Result Card Detailed Results Table Wire Size Reference Table |

How the Wire Size Calculation Works

Wire sizing involves two parallel checks: current-carrying capacity (ampacity). The calculator determines which constraint requires the larger wire and recommends that size.

The Core Formula

For voltage drop-based sizing, the calculator uses this equation:

Cross-sectional Area (mm²) = (2 × ρ × L × I) / V

Where:

ρ (rho) = Conductor resistivity (1.72 × 10⁻⁸ Ω·m for copper, 2.65 × 10⁻⁸ Ω·m for aluminum)
L = One-way cable length in meters
I = Load current in amperes
V = Maximum allowable voltage drop in volts

For three-phase circuits, the formula changes slightly—the factor of 2 becomes √3 (approximately 1.732) since there's no neutral return path in balanced loads.

Temperature Adjustment

Copper's resistivity increases with temperature. The UAE's ambient temperatures often exceed 45°C, which means cables carry less current than their rated capacity. The calculator applies a temperature coefficient to adjust resistivity:

ρ = ρ_20°C × (1 + 0.00393 × (T – 20))

This adjustment is essential for accurate sizing in hot environments. DEWA and ADDC regulations reference BS 7671 derating factors for installations in the UAE's climate. Understanding how temperature affects your electrical current calculations ensures compliance with local codes.

Important Considerations

The calculator provides minimum recommended sizes. Always round up to the next standard wire gauge, and consider future load growth. For grouped cables in trunking or conduits, additional derating applies—multiple cables sharing space generate combined heat that reduces each cable's capacity.

Example 1: Villa Air Conditioning Circuit in Dubai

Scenario: Ahmed is installing a split AC unit in his villa in Dubai Marina. The unit draws 20 amperes on a single-phase circuit. The cable run from the distribution board to the outdoor unit is 25 meters.

Calculation:

Maximum voltage drop at 4%: 230V × 0.04 = 9.2V
Using copper conductor at 40°C adjusted resistivity: 1.86 × 10⁻⁸ Ω·m
Area = (2 × 1.86 × 10⁻⁸ × 25 × 20) / 9.2
Area = 2.02 mm²

Result: Minimum wire size is 2.02 mm². The next standard size is 2.5 mm². However, checking ampacity tables, 2.5 mm² copper handles only 24A under ideal conditions. With derating for UAE ambient temperature, this drops to approximately 21A—just above the 20A load. For safety margin, Ahmed should use 4 mm² cable. For related AC sizing, check out the air conditioning capacity tool.

Example 2: Office Lighting Circuit in Abu Dhabi

Scenario: Fatima is designing a lighting circuit for a commercial office in ADGM (Abu Dhabi Global Market). The circuit supplies 15 amperes of LED lighting fixtures on single-phase . Total cable length is 40 meters.

Calculation:

For lighting, ADDC requires maximum 3% voltage drop: 230V × 0.03 = 6.9V
Using copper at 35°C: resistivity ≈ 1.82 × 10⁻⁸ Ω·m
Area = (2 × 1.82 × 10⁻⁸ × 40 × 15) / 6.9
Area = 3.17 mm²

Result: Minimum size is 3.17 mm², so Fatima needs 4 mm² copper cable. This satisfies both voltage drop requirements and provides adequate ampacity for the lighting load.

Example 3: Industrial Motor Feed in Sharjah

Scenario: A warehouse in Sharjah Industrial Area needs to connect a 15kW three-phase motor operating at . The motor is located 80 meters from the main distribution board.

Calculation:

Motor full-load current: 15,000W / (√3 × 400V × 0.85 power factor) ≈ 25.5A
Maximum 5% voltage drop for power loads: 400V × 0.05 = 20V
Three-phase formula: Area = (√3 × ρ × L × I) / V
Area = (1.732 × 1.86 × 10⁻⁸ × 80 × 25.5) / 20
Area = 3.29 mm²

Result: While voltage drop suggests 4 mm² is sufficient, motor circuits require sizing for starting current (typically 6-8 times running current) and SEWA regulations mandate minimum conductor sizes. A 6 mm² three-core armoured cable is the practical choice. Verify motor sizing with the kilowatt to kilovolt-ampere converter for accurate load assessment.

Authority-Specific Requirements

Different emirates follow their distribution company regulations:

DEWA (Dubai): Maximum 4% voltage drop from supply point to final circuit. Minimum 1.5 mm² for lighting, 4 mm² for socket outlets. Reference: DEWA Regulations for Electrical Installations
ADDC (Abu Dhabi): Follows Abu Dhabi Department of Energy Electricity Wiring Regulations 2020. Reference: Department of Energy Abu Dhabi
SEWA (Sharjah): Aligns with BS 7671 and local amendments
FEWA (Northern Emirates): Federal authority covering Ajman, Umm Al Quwain, Ras Al Khaimah, and Fujairah

Common Mistakes to Avoid

Professionals and DIY installers frequently make these errors:

Ignoring temperature derating: A cable rated 32A at 30°C may only carry 27A at 45°C ambient temperature
Forgetting cable grouping factors: Multiple cables in conduit require derating—six cables together may each carry only 57% of their individual rating
Using aluminum sizes for copper: Aluminum requires approximately 1.6 times the cross-section of copper for equivalent current capacity
Neglecting route length: Measure the actual cable path, not straight-line distance between points

Expert Tips

Plan for future expansion by sizing cables one step larger than calculated. For critical equipment, consider redundant circuits. Always verify calculations with a licensed electrical consultant before installation, especially for loads exceeding 100 amperes. For comprehensive utility planning, explore the Dubai electricity consumption estimator to understand your overall power needs.

Get Started with Accurate Wire Sizing

Use the calculator above to determine the correct wire size for your next electrical project. Enter your current, voltage, cable length, and installation conditions for instant results. For complex installations involving multiple circuits or specialized equipment, consult a DEWA or ADDC-approved electrical contractor.

This calculator is provided by as a free resource for electricians, engineers, and property owners. Bookmark this page for quick reference during your projects. Explore our electrical and utility calculators for additional tools including cable sizing guides, wattage computations uninterruptible power supply planners.

Wire Size Calculator UAE – Accurate Cable Sizing